diff --git a/backend/open_webui/migrations/versions/8452d01d26d7_add_chat_message_table.py b/backend/open_webui/migrations/versions/8452d01d26d7_add_chat_message_table.py
index 567f7d673a..ea95d08f12 100644
--- a/backend/open_webui/migrations/versions/8452d01d26d7_add_chat_message_table.py
+++ b/backend/open_webui/migrations/versions/8452d01d26d7_add_chat_message_table.py
@@ -21,6 +21,39 @@ down_revision: Union[str, None] = "374d2f66af06"
 branch_labels: Union[str, Sequence[str], None] = None
 depends_on: Union[str, Sequence[str], None] = None
 
+BATCH_SIZE = 5000
+
+
+def _flush_batch(conn, table, batch):
+    """
+    Insert a batch of messages, falling back to row-by-row on error.
+
+    Tries a single bulk insert first (fast path). If that fails (e.g. due to
+    a duplicate key), falls back to individual inserts wrapped in savepoints
+    so the rest of the batch can still succeed.
+    """
+    savepoint = conn.begin_nested()
+    try:
+        conn.execute(sa.insert(table), batch)
+        savepoint.commit()
+        return len(batch), 0
+    except Exception:
+        savepoint.rollback()
+        # Batch failed - insert one-by-one to isolate the bad row(s)
+        inserted = 0
+        failed = 0
+        for msg in batch:
+            sp = conn.begin_nested()
+            try:
+                conn.execute(sa.insert(table).values(**msg))
+                sp.commit()
+                inserted += 1
+            except Exception as e:
+                sp.rollback()
+                failed += 1
+                log.warning(f"Failed to insert message {msg['id']}: {e}")
+        return inserted, failed
+
 
 def upgrade() -> None:
     # Step 1: Create table
@@ -88,18 +121,21 @@ def upgrade() -> None:
         sa.column("updated_at", sa.BigInteger()),
     )
 
-    # Fetch all chats (excluding shared chats which have user_id starting with 'shared-')
-    chats = conn.execute(
+    # Stream rows instead of loading all into memory:
+    # - yield_per: fetches rows in chunks via cursor.fetchmany() (all backends)
+    # - stream_results: enables server-side cursors on PostgreSQL (no-op on SQLite)
+    result = conn.execute(
         sa.select(chat_table.c.id, chat_table.c.user_id, chat_table.c.chat).where(
             ~chat_table.c.user_id.like("shared-%")
-        )
-    ).fetchall()
+        ).execution_options(yield_per=1000, stream_results=True)
+    )
 
     now = int(time.time())
-    messages_inserted = 0
-    messages_failed = 0
+    messages_batch = []
+    total_inserted = 0
+    total_failed = 0
 
-    for chat_row in chats:
+    for chat_row in result:
         chat_id = chat_row[0]
         user_id = chat_row[1]
         chat_data = chat_row[2]
@@ -139,39 +175,43 @@ def upgrade() -> None:
             if timestamp < 1577836800 or timestamp > now + 86400:
                 timestamp = now
 
-            # Use savepoint to allow individual insert failures without aborting transaction
-            savepoint = conn.begin_nested()
-            try:
-                conn.execute(
-                    sa.insert(chat_message_table).values(
-                        id=f"{chat_id}-{message_id}",
-                        chat_id=chat_id,
-                        user_id=user_id,
-                        role=role,
-                        parent_id=message.get("parentId"),
-                        content=message.get("content"),
-                        output=message.get("output"),
-                        model_id=message.get("model"),
-                        files=message.get("files"),
-                        sources=message.get("sources"),
-                        embeds=message.get("embeds"),
-                        done=message.get("done", True),
-                        status_history=message.get("statusHistory"),
-                        error=message.get("error"),
-                        created_at=timestamp,
-                        updated_at=timestamp,
-                    )
-                )
-                savepoint.commit()
-                messages_inserted += 1
-            except Exception as e:
-                savepoint.rollback()
-                messages_failed += 1
-                log.warning(f"Failed to insert message {message_id}: {e}")
-                continue
+            messages_batch.append({
+                "id": f"{chat_id}-{message_id}",
+                "chat_id": chat_id,
+                "user_id": user_id,
+                "role": role,
+                "parent_id": message.get("parentId"),
+                "content": message.get("content"),
+                "output": message.get("output"),
+                "model_id": message.get("model"),
+                "files": message.get("files"),
+                "sources": message.get("sources"),
+                "embeds": message.get("embeds"),
+                "done": message.get("done", True),
+                "status_history": message.get("statusHistory"),
+                "error": message.get("error"),
+                "usage": message.get("usage"),
+                "created_at": timestamp,
+                "updated_at": timestamp,
+            })
+
+            # Flush batch when full
+            if len(messages_batch) >= BATCH_SIZE:
+                inserted, failed = _flush_batch(conn, chat_message_table, messages_batch)
+                total_inserted += inserted
+                total_failed += failed
+                if total_inserted % 50000 < BATCH_SIZE:
+                    log.info(f"Migration progress: {total_inserted} messages inserted...")
+                messages_batch.clear()
+
+    # Flush remaining messages
+    if messages_batch:
+        inserted, failed = _flush_batch(conn, chat_message_table, messages_batch)
+        total_inserted += inserted
+        total_failed += failed
 
     log.info(
-        f"Backfilled {messages_inserted} messages into chat_message table ({messages_failed} failed)"
+        f"Backfilled {total_inserted} messages into chat_message table ({total_failed} failed)"
     )